How to download and add the repo key, add the repo URL to the sources list, update the apt cache and use apt to install Virtual Box.
Then I showed how to find and launch the GUI program in the applications folder and finally I showed how to verify the installation in the CLI and some important commands and arguments on how to create and start VMs in the CLI.
Useful links:
https://www.virtualbox.org/
Join my Pop! OS Linux group on Facebook:
/ poposlinux